The new US embassy in London is a "signal to the world" that the relationship between the UK and the United States is strong and going to grow, the American Ambassador has said.

Woody Johnson expressed his desire to have Donald Trump at the opening of the new headquarters on London's South Bank in January, but emphasised that a date had not yet been set for the President's visit to Britain.

Mr Trump had tasked him with strengthening the special bond between the two countries, he said, adding that the president recognised the UK was "the gateway to Europe".

He said: "President Trump wants to work more closely than ever with the UK and it will make both of our countries more prosperous and secure.

"So the new embassy is a signal to the world that this special relationship that we have is stronger and is going to grow and get better. He mentioned that to me himself, he said 'I want you to make it stronger', and I intend to do that if I can.'"